Answer to Question #15892 in Mechanics | Relativity for stanley

Question

a speedy racer is drivint his car on a linear racing strip try to test out his cars specifications.he starts running the diagnostics while his car is travelling at a rate of 5 m/s. over the course of the next 5.4 seconds, he quadruples his speed and crosses the finish line. how far away was the finish line from where he started his diagnostic?

Answer 1

The average speed of a car after running the diagnostics till crossing the finish line was

V = (4*5[m/s] + 5[m/s])/2 = 12.5[m/s].

So, the distance to the finish line from where he started his diagnostic was

D = 12.5[m/s]*5.4[s] = 67.5 metres.